When natural beauty just isn’t cutting it . . .

Ines Ligron is the ultimate Miss Universe insider, and she does not believe much in secrets. One of her favorite stories is of a contestant who could have won but opted for last-minute cosmetic surgery, and thus was barely able to lift her arms when she went before the judges.

Even her own protege — current Miss Universe Riyo Mori — had work done.

“But just a little plumper in the lips,” Ligron said.

Handpicked by real estate billionaire Donald Trump, who took over the Miss Universe pageant a decade ago, Ligron is possibly the world’s leading trainer of beauty contestants, having coached Mori to the crown last year — Japan’s first since 1959 — and Kurara Chibana to the first runnerup slot the year before.

Getting on Ligron’s list can mean overnight stardom.

Hundreds of millions of people around the world watch the annual contest to be held this June, in which women from 80 countries compete. Mori is currently hopping the globe between sessions on an MTV reality show, while Chibana has become a major celebrity in Japan, gracing magazine covers, cohosting variety programs and endorsing dozens of products.

Ligron, a vivacious and successful businesswoman in her own right, is now whittling down a list of thousands of women vying to be her pick when the contest is held in Vietnam. Along with Japan, she will be training the South Korean entry. After that, she wants to coach in her native France.

“These girls are like babies when they come to me,” Ligron said. “When I’m done, they have their college diplomas.”

But winning the diamond-and-pearl crown comes with a price.

And often a slice.

It’s time to take a walk.

In one of the last training sessions before Ligron names her final batch of contestants for the Miss Japan contest, whose winner represents Japan at Miss Universe, she takes about a dozen of her favorites out to a crowded crosswalk in a fashionable part of town.

The women strut back and forth across the street, then hold an impromptu fashion show — in their street clothes — on the stairs outside a large clothing store. Within minutes, a crowd of about 200 has gathered. A guard warns Ligron that he is concerned it might get out of hand.

Mission accomplished.

They laugh and clap, and head back to Ligron’s office.

“With a fashion model on the catwalk, it’s about the clothes,” Ligron said. “With Miss Universe, it’s all about the woman herself.”

After passing a mass audition, the competitors go through sessions with Ligron on speaking and posture, fashion and makeup, presentation and attitude. It’s often brutal — Ligron turned away one contestant, a high fashion model, because the woman refused to gain weight.

“I know some people don’t respect beauty contests,” she said. “But this one really appeals to me. It’s not just about being cute and pretty. You have to be cool and smart. Miss Universe is the woman I want to be.”

“I told her I could change,” Nishigaki said. “And I did. I dyed my hair, I changed my clothes, my walk, my look. I think I have what it takes.”

She is stunning.

There is just one thing.

She hates her ears.

Like steroids in sports, surgical enhancements are the dirty little secret of the beauty pageant world. But, unlike steroids, artificial enhancements in beauty competition are not banned, or even particularly frowned upon.

Ligron said it is commonplace for contestants to remove a rib or two to make their waist smaller, to have breast augmentation, nose reshaping or eyebrow lifting. Complete reworking of the teeth is also de rigueur.

“I guarantee you, of the five women on the stage, most of them had plastic surgery,” she said of this year’s Miss Universe final. Along with Mori, the other four finalists were from the U.S., Venezuela, Brazil and South Korea.

In the United States, the subject caused a stir in 1983 when it was revealed that Miss America Debra Maffett had undergone surgery on her nose and breasts after previously losing the Miss Texas title. The Miss USA pageant has no limits on cosmetic surgery, although it has allowed contestants to use padding since 1990 to discourage breast implants.

Ligron makes all of her proteges sign a statement that they were not encouraged by her staff to undergo surgery of any kind. They must also inform her of any work they have had done in the past.

Ligron said one concern is health — going under the knife involves an element of risk, and organizers do not want to get sued for encouraging a botched nose job. But another concern is that, if a contestant hits it big, before-and-after photographs are bound to surface.

“If it’s very obvious, we don’t want girls who look like Michael Jackson,” she said. “Imagine if a girl has an operation and something goes wrong. This would be a big scandal.”

But it is complicated.

Ligron says that if, for example, an otherwise beautiful woman with floppy ears gets them fixed, on her own, without coaxing, well, “I’m so happy. Thanks, you know?

“It’s the girl’s decision,” she shrugged. “I cannot control that.”

To many contestants, that’s a green light.

Rita Lamah, the second runnerup in the 2003 Miss Lebanon contest, said she feels contestants should be free to choose whether or not they opt for cosmetic surgery.

“Nowadays, through the plastic surgery, everyone can be beautiful, which, I believe, is definitely a great achievement,” she said.

Ligron said surgery on the eyelids — to make the eyes appear bigger and more Western — is especially common with Asian women. Enhancements are no guarantee of success, though.

The contestant who could not lift her arms — because she had just had her breasts enlarged — was vying for the Japan title last year. She was among the first that Ligron weeded out.

Nishigaki, meanwhile, is still undecided about whether she will keep her earlobes.

“But I think that getting them fixed could make me more confident,” she said. “And that’s what really counts.”

When Riyo Mori walks into a room, she owns it.

Almost brash in her self-assurance, she savors her role, being in front of the camera, commanding attention. Physically, she was born — not sculpted — for the part. She towers over most of the men around her (she’s 1.75 meters in her bare feet), and has a leggy, dancer’s body.

Other than the lips, which are now back to normal, she has had no work done.

“I’m all natural,” she said recently over a quick lunch in Ligron’s apartment, where she and Chibana were doing a photo shoot for the cover of a book Ligron was working on. It was a brief stop — Mori was en route to a fashion show on the Great Wall of China.

Natural gifts notwithstanding, Mori admitted she has gone through a transformation under Ligron’s tutelage.

“I was just a girl from the countryside in Japan, I didn’t know anything,” Mori said. “I was watching her, everything she does. A woman. She’s very cool. Like a live textbook.”

Since Trump took over, the Miss Universe contest and its sisters — Miss USA and Miss Teenage USA — have gone through a major makeover as well.

They have been retooled from a showcase of male fantasies — Miss Universe started out as a bathing suit competition in California in 1952 — to an event that appeals mainly to women.

Contest organizers say that makes good business sense because many of the sponsors are looking to sell products to women. And the winners are more likely to endorse cosmetics or fill the pages of fashion magazines than they are to be shilling beer.

“Back in the day, it was all this, they were on a pedestal, they looked pretty with their pretty gowns and their pretty hair, but they really didn’t speak. There was a lack of substance,” said Roston Ogata, who works for the Trump organization as a talent director. “We are definitely trying to turn that around, to push the envelope a lot more.”

Last year’s Miss USA, Tara Conner, pushed the envelope a bit too far — Trump allowed her to keep her crown only after she agreed to go into rehab after admitting in a tearful news conference to heavy, underage drinking.

So far, Mori’s reign has been scandal-free. But she has also dropped the demure, girl-next-door shtick.

In apologizing for running off before finishing her salad, Mori explained that she was late for a seminude shoot — her second.

“I’m comfortable with it,” she said. “It’s for charity.

“In Japan, for lots of girls, it’s not so good to have confidence. It’s good to be conservative, very quiet,” she said. “It’s the culture in Japan, women shouldn’t show off. Like a woman’s always behind the man, women are more quiet, they don’t say their opinion. But I have opinions, and I can talk.

“I’m a performer, I’m a dancer,” she said. “Once I’m on the stage, ‘poof,’ I can change.”